Chlorine generator and method

ABSTRACT

A chlorine generator is disclosed as including an assembly for an electrolytic cell generating the chlorine and a separate assembly for feeding the chlorine gas into a body of water. The cell assembly preferably includes two separate electrolytic solutions separated by an ion permeable membrane, such that an anode and a cathode are positioned on each side of the membrane. The gas feed assembly is in fluid communication with the cell housing by two separate conduits which accommodate the flow of gas from the cell to the feed assembly, within which the gases are accumulated and intermixed with a portion of water which has been diverted from the main body of water to flow through the feed assembly and then back to the main body of water.

CROSS-REFERENCE TO RELATED PATENT AND RELATED PATENT APPLICATION

The present invention is related to a chlorine generator disclosed inApplicant's prior U.S. Pat. No. 4,097,356 filed on Sept. 8, 1977 andgranted on June 27, 1978, which patent is incorporated herein byreference for all purposes. Additionally, the housings for the inventionof this application are disclosed in pending design application No.019,850, filed Mar. 12, 1979, which is likewise incorporated herein byreference for all purposes.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates generally to a method and apparatus for thegeneration of chlorine gas for supply to a body of water, such as aswimming pool, and more particularly to a system including a novelarrangement of an electrolytic cell gas generator and a system forfeeding the gases into a flowing stream of water diverted from the mainbody of water.

2. The Prior Art

The generation of chlorine and its introduction to a water reservoirsuch as a swimming pool, a cooling tower and the like is the subject ofvarious patents, including U.S. Pat. Nos. 3,351,542 to Oldershaw,3,669,867 to Kirkham, 2,887,444 to Lindstaedt, and 3,223,242 to Murray.However, these patents disclose generally complicated chlorinegeneration systems such as the one shown in the Murray patent. Oldershawincludes a system which includes a conceivably dangerous electrolyticsolution, such as hydrochloric acid, whereas Lindstaedt requires theaddition of sodium chloride to the stream of water which flows directlyinto the pool. Obviously, the Lindstaedt arrangement and others like itwhere sodium chloride is injected into a body of water which is to beused by a human is highly undesirable. Kirkham includes a coolingelement for one of its electrode compartments within the electrolyticcell, likewise making that structure unnecessarily complicated.

Other known patents relating to electrolytic cells include U.S. Pat.Nos. 3,117,066 and 3,291,708 to Juda, 4,035,254 to Gritzner, 4,010,085to Carlin and 3,975,284 to Lambert.

U.S. Pat. No. 3,361,663 to Murray even discloses a system for injectinga sanitizing gas into a flowing stream of water for use in a swimmingpool. However, the present invention distinguishes significantly fromthe Murray system to provide the advantages which will be more fullyexplained and appreciated in further portions of this disclosure.

Additionally, ion permeable membranes used in previous chlorinegeneration systems have ranged from, for example, asbestos diaphragms toperfluorosulfonic acid membranes such as described in U.S. Pat. No.3,909,378 to Walmsley. The perfluorosulfonic acid membranes as disclosedin the latter patent have also been described in conjunction with achlorine generator system in such publications as du Pont Magazine,May-June, 1973, pp. 22-25 and in a paper entitled "Perfluoronated IonExchange Membranes" by Grot, Munn and Walmsley, presented to the 141STNational Meeting of the Electro-Chemical Society, Houston, Tex., May7-11, 1972. Additional patents relating to perfluorosolfonic acidmembranes used in electrolysis reactions include U.S. Pat. Nos.3,793,163 to Dotson, 3,775,272 to Danna, and 4,010,085 to Carlin.Another known patent relating to diaphragms for electrolytic cells isU.S. Pat. No. 3,853,720 to Korach.

All the referenced patents and articles referred to above areincorporated herein by reference for all purposes.

Various problems are associated with the prior art type generators. Forexample, the Lindstaedt patent discloses a system where sodium chlorideis injected into the main body of water, and is undesirable aspreviously discussed. The disclosure of Murray, U.S. Pat. No. 3,361,663,for example, accumulates the gases generated in the electrolytic celland conveys them by one single line for injection into the flowingstream of water, and potentially creates a hazard of mixing twoincompatible gases through the single conduit conveying line. Moreover,the Murray system does not include any provision for sensing thepressure of water flow from the pool filtration cycle, such that gaseswould continue to be generated even if water pressure were lost fromthat filtration cycle.

SUMMARY OF THE INVENTION

These and other problems of the prior art are overcome by the presentinvention, which in one aspect includes a combination chlorinegeneration and supply assembly. The chlorine generation assemblyincludes as electrolytic cell having a housing enclosing an anode and acathode for the generation of gases, including chlorine, and means foraccomodating the aspiration of the gases from the housing for supply tothe gas feed system.

The gas feed system includes a housing for receiving water from a bodyof water to be chlorinated and an interior chamber constructed toreceive chlorine from the electrolytic cell, to receive water from amajor chamber within the feed system, and to accomodate the admixing ofthe water and the chlorine for injection back into the main body ofwater. In the preferred structural arrangement of the gas feed system,the feed system housing includes a top enclosure member and a major bodycomponent having a bottom, two sides and two ends. The admixing chamberfor the water and the chlorine is formed at a first end of the housingby a plate attached to that end at a position toward the top of thehousing body such that the plate extends downwardly and toward the otherend of the housing. The plate terminates above the bottom to form theadmixing chamber between it and the first end of the housing and toprovide a passageway for water into the admixing chamber.

The preferred arrangement for the electrolytic cell includes a separatordivider to form two separate regions associated with an anode and acathode. A conduit extends from each of these respective regions to theadmixing chamber to separately conduct the gases generated on each sideof the electrolytic cell. Most preferably, the electrolytic cell isdivided by an ion permeable membrane, formed of a perfluorosulfonic acidpolymer, and held in position by a plastic frame.

In the arrangement including the two separate conduits extending fromthe gas generator to the feed system, a filter is interposed in the linefrom the cathode in order to remove at least some of the sodiumhydroxide conveyed in that line with hydrogen gas from the cathodechamber. The filter includes an enclosure receiving a conduit portionextending from the cell to the filter and a separate conduit portionextending from the filter to the gas feed assembly. With thisarrangement, hydrogen and entrained moisture are conveyed to the filter,moisture with entrained sodium hydroxide are deposited in the filter,and hydrogen gas is then conveyed to the gas feed assembly.

In another perferred aspect of the invention, a liquid communicationcoupling is provided on the gas feed system to receive water from adesired body of water. This coupling includes a first flow line forsupplying water to the gas feed system and a second flow line forsupplying water to the electrolytic cell so that the cell can be filledor refilled as desired. Most preferably, a flow conduit extends from thesecond flow line in the coupling and then branches into two sectionswhich extend to the separate sides of the electrolytic cell. Adual-purpose valve is provided at the point of interconnection betweeneach respective branch line with the cell, such that the valvesselectively supply water to the respective regions of the cell and alsosimultaneously vent the regions above each electrolytic region as wateris being supplied to that region.

Another aspect of this invention includes the provision of a means forsensing the liquid water pressure from the source within the coupling.In the event that an extreme loss of pressure is encountered, theelectrolytic cell is deactivated so that gases will not continue to begenerated without there being water circulated through the gas feedsystem to convey the gases into the main body of water.

The method aspect of this invention relates to the manner of injectingchlorine into a desired stream of water. This is accomplished bysimultaneously, electrolytically generating chlorine gas and hydrogengas within an electrolytic cell comprised of an anode and a cathodeimmersed in an aqueous electrolytic solution. The chlorine and hydrogengases are collected in respective separate regions in the electrolyticcell, and are then aspirated in response to the naturally occuringpressure and separately conveyed through two individual conduits to agas feed system, which includes an enclosed housing and an interiorchamber into which the gases are directly conveyed. The gases areinjected into the desired stream of water by flowing a portion of thatstream into the enclosed housing of the gas feed system and into theinterior chamber for admixing, whereupon the water and admixed chlorineand hydrogen are then flowed back to the desired stream of water.

When this method and apparatus are used with a swimming pool, theelectrolytic cell is typically selectively activated to generate thechlorine and hydrogen gases for supply to the gas feed system. Mostpreferably, water is diverted from the pool filtration cycle for flowinto the gas feed system for admixing with the gases and then for flowback to the filtration cycle.

Accordingly, the present invention provides numerous advantages in thechlorination of water. Among these advantages are:

1. No harmful salts or acids are added to the main body of water.

2. Sodium hydroxide is removed from the hydrogen gas to further reducethe injection of impurities into the main body of water.

3. As a result of the first two advantages, water appearance is improvedto provide an enhanced clarity and sparkle.

4. Storage and handling of potentially dangerous chemicals areeliminated.

5. The costs for operating and chlorinating a pool are reduced.

6. The disclosed system is durable and designed for a long operatinglife and essentially trouble-free service.

7. The disclosed system is automated for simplicity of use.

8. The system is versatile for use in many environments such as swimmingpools, water towers, water tanks and reservoirs, cooling tanks, solarheating systems, hot baths, and food processing plant sterilizationsystems.

9. Moreover, the present system is designed to make the chlorinegeneration system more efficient than the system disclosed inApplicant's prior U.S. Pat. No. 4,097,356. For example, the disclosedembodiment of this invention includes a gas feed system different fromthat disclosed in Applicant's prior patent, such that an improved systemis provided for better injecting the chlorine gas into the flowingstream of water, such that simplified servicing and operation isprovided, and such that a low pressure is developed above theelectrolytic cell so that the generation of gases will not be hampered.

10. The present system has the capability of developing significantamounts of chlorine for establishing desired levels of chlorineconcentration in water for various disinfectant purposes. For example,it is now felt that concentrations of three parts per million or more ofchlorine may be effective in killing Legionnaire's bacteria found incooling tower sprays.

11. The system is designed for safety by including sensing equipment tomaintain small quantities of chlorine within both the generator and thegas feed.

These and other advantages and meritorious features of this inventionwill be more fully appreciated and understood from the followingdetailed description and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic illustration, showing the gas generation and feedsystem as used in connection with a circulating pool filtration cycle.

FIG. 2 is a vertical, particle cross-sectional view of the electrolyticcell housing.

FIG. 3 is a top plan view of the electrolytic cell housing with the lidremoved.

FIG. 4 illustrates an embodiment of a dual-purpose valve foraccomodating the introduction of water into the electrolytic cellregions while at the same time relieving pressure from the electrolyticcell.

FIG. 5 is a side elevational view of the gas feed assembly, illustratingthe fluid coupling member receiving water from the pool filtration cycleand supplying water both to the gas feed and to the electrolytic cell.Additionally shown are the float control valve for regulating theintroduction of liquid into the gas feed system and the interior gastrap for admixing the chlorine gas with water.

FIG. 6 is an end elevational view of the gas feed assembly, illustratingthe positions of the conduits leading to and exiting from the gas trapregion of the gas feed assembly.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention relates to a system for generating and feedingchlorine gas to a desired body of water. FIG. 1 illustrates one of thetypical intended uses for this invention as including a swimming pool.The pool filtration and circulation system is conventional and thereforeforms no part of the present invention. In such a system, water iswithdrawn from pool 10 into flow line 12 by a suction created by pump14, which is powered by drive member 16. As shown, water flows throughpipe 12 into a lint strainer 18 and then into the pump 14 where theflowing water is pumped under pressure through a flow line 20 into afilter 22 and then through return flow line 24 for introduction backinto the pool.

In accordance with the present invention, a part of the water underpressure in flow line 20 is diverted into a flow line 30 for flow to aliquid coupling member 50 attached to a gas feed system 60. As will bemore fully explained in later portions of this disclosure, water ismetered into the gas feed system 60 by a float controlled valve, flowsinto a gas trap region 62 formed by a downwardly depending plate 64,picks up chlorine and hydrogen gas supplied to the gas trap 62, andflows out of the gas feed system into flow line 32 for introduction backinto the pool filter cycle into flow line 12. As will be appreciated,the flow of water through conduit 30 and then back into the filtrationsystem by conduit 32 will occur without the provision of any auxiliarypumping means, because a positive pressure is established in flow line20, whereas a suction is established in flow line 12 to draw the waterback into that line.

The gas generator 100 is depicted schematically with a vertical dashedline to indicate that this member is internally divided into twocompartments which respectively include a cathode generating hydrogenand an anode generating chlorine. Chlorine flows from its respectivechamber as a result of a positive pressure created in that chamber bythe generation of gas and into the gas feed system by a tubular flowconduit 102. Likewise, hydrogen flows from its respective internalchamber in the gas generator into the gas feed by a tubular flow conduit104. An optional filter 110 may be interposed within the flow line 104for the purpose of removing impurities, such as sodium hydroxide. Thisfilter 110 is composed of a closed internal chamber receiving an end ofthe branch line 104 extending from the gas generator and also receivingthe end of the branch line 104 which extends from the filter to the gasfeed. In the operation of this system, hydrogen with entrained moistureand sodium hydroxide flow into the filter 110, where at least a portionof the moisture and the sodium hydroxide are deposited. Then thehydrogen gas flows back out of the filter and into the terminal portionof flow line 104 into the gas feed system. In actual practice, thefilter 110 may include a one-gallon plastic blow-molded container, suchas is used for packaging milk, with the plastic top for the galloncontainer including openings to receive the two end portions of flowconduit 104.

The anode and cathode of the electrolytic cell within the gas generator100 are powered by D.C. current provided by a power means 200. Asdisclosed in Applicant's prior U.S. Pat. No. 4,097,356, it is notnecessary to supply the D.C. current to the generator continuously formost purposes, such as with a home pool, and therefore it is desirableto activate the gas generator intermittently. Accordingly, a timer 202is provided to selectively open and close a gate 204 to establishelectric current flow from the power means through parallel branch lines206 and 208 which are interconnected with an anode and cathode (notshown in FIG. 1). Since the gas generator of the present invention maybe used in various embodiments, it is also desirable to include arheostat regulator (not shown) to vary the amperage from the powersource in order to regulate the gas generation. It has been found thatthe provision of 20 amps of D.C. current to a gas generator in home pooluse is sufficient to establish the optimum 0.6 to 1.0 part per millionchlorine content in water with the intermittent operation of theelectrolytic cell.

FIG. 1 further illustrates a flow line 52 extending from the liquidconnector 50 and branching into separate flow lines 54 and 56 whichextend to valves 90 and 90A. These flow lines 52, 54 and 56 are providedso that water may be supplied indirectly from the pool water circulationsystem by way of flow line 30 in order to fill or refill the respectiveanode and cathode compartments within the gas generator.

The preferred embodiment of valve 90 is illustrated in FIG. 4 and isintended to be representative of both valves 90 and 90A. The purpose ofthis valve is not only to accomodate the flow of water under pressureinto one of the gas generator compartments, but also to accomodate therelieving of pressure within the interior compartment as water isintroduced. The valve includes a body 91 having a vertical cylindricalopening 92 which receives a rotatable, essentially cylindrical valveregulator 93 held in position by snap ring 94 and sealed by O-rings 95.A valve stem 93A is formed at the bottom of the rotatable valveregulator 93 to accomodate manual rotation. Openings 96A and 96B in thevalve regulator are aligned with openings in the valve body throughthreaded, essentially cylindrical connection ports 97A and 97B whichrespectively provide a pressure relief and a connection for water supplyline 56. Similarly, openings 96A and 96B are aligned with openingsextending through threaded, essential cylindrical connectors 98A and 98Bwhich are adapted for connection through openings in the wall of gasgenerator 100.

In the operation of valve 90, water is continuously available throughline 56 as a result of the construction of coupling member 50, as willbe more fully disclosed in further portions of this application. When itis desired to either fill or refill the appropriate chamber in the gasgenerator, valve stem 93 is manually rotated approximately 90° from theposition shown in FIG. 4 so that openings 96A and 96B are aligned withthe openings in cylindrical members 97A-98A and 97B-98B, respectively.In this position, water flows through the opening in cylindrical member87B, through opening 96B, through the opening in cylindrical member 98Band into the gas generator. Simultaneously, pressure is relieved by theopening through member 98A, the opening 96A and the opening in member97A. By this arrangement, an undesirable pressure build-up is obviatedduring a water supply and filling operation.

Referring now more particularly to FIGS. 2 and 3, the gas generationhousing is illustrated with greater particularity. This housing includesa plastic, injection molded base 120 having integral support legs 122 ateach of its bottom four corners. In general, the housing furtherincludes a bottom 124 and upwardly extending sidewalls 126 which flareoutwardly and terminate at an upper peripheral flange 127, upon which aclosure lid 128 is securely fastened to establish internally sealedcompartments within the housing 120. Also, in general, the housing 120includes a pair of drain openings 130 and 132 which are closed byappropriate stop members. An optional sight opening 134 is also providedto receive a transparent viewing member. Openings 136 and 138 areprovided to receive the cylindrical members 98A and 98B of valve 90,whereas openings 140 and 142 are provided to similarly receive theidentical members of valve 90A. An opening 144 is provided to receiveone end of the flow conduit 102 for supplying chlorine gas from thegenerator to the gas feed. Similarly, an opening 146 is provided toreceive an end of flow conduit 104 for supplying hydrogen from thegenerator to the filter 110 and then to the gas feed system.

Parallel projections 150 and 152 are provided as illustrated to extenddownwardly along the back wall of the generator then across the interiorbottom wall of the generator and up the inside of the front wall of thegenerator in order to establish a channel for receiving and retaining adivider member 160. This divider is configured and sized to extend fromthe bottom of the generator wall up to an abutting relationship with thelid 128 and to extend from the interior of the front to the back wallsin order to divide the interior of the housing member 120 into twoseparate chambers. Further, this divider 160 will preferably be injectedmolded to support an ion permeable membrane to accomodate theelectrolytic action within the generator. The ion permeable membrane ispreferably comprised of a fluoronated polymer such as, for example, aperfluorosulfonic acid polymer manufactured by E. I. du Pont Co. andsold under the trademark Nafion. As discussed in applicant's prior U.S.Pat. No. 4,097,356, such a material has the characteristic of permittingthe transfer of sodium ions across the membrane from the anodecompartment to the cathode compartment, while preventing the intermixingof the electrolytic solutions in the respective compartments.

As best seen in FIG. 3, three threaded openings 170 are provided in thebottom wall of the housing 120 and receive threaded ends of elongatedcylindrical anodes 172. Preferably, the anodes are formed of carbonmaterial, but may be formed of any material such as gold, silver orplatinum to generate the desired chlorine gas during operation.

Similarly, three additional threaded openings 174 are provided in thebottom wall of the housing 120 and receive the threaded ends ofrespective cathodes 176. These cathodes are preferably formed ofstainless steel material but likewise may be formed of carbon, carbonsteel or other suitable metals as may be desired in order to enhance theproduction of chlorine gas in the anode compartment. In operation,hydrogen gas will in actuality be formed in the cathode compartment.

The electrolytic cell formed by the gas generator set-up as previouslydescribed will be operated in the following fashion. Values 90 and 90Awill be manually operated to accomodate the flow of water from liquidconnector 50 through lines 52, 54 and 56 into the anode and cathodecompartments within the housing 120. During this filling operation, airwill be vented through the openings 98A, 96A, and 97A to prevent apressure build-up. When water flows through vent 97A, it is known thatthe chamber is full, and therefore the valves are then manually closed.Sodium chloride is then added to the anode chamber by removing a cap 180from lid 128. The system is then ready for operation through the supplyof D.C. current from the power means as appropriately operated by atimer mechanism 202. As D.C. current is supplied, chlorine gas isgenerated by the anodes 172 and are accumulated in a chamber region 190formed between the top surface of the liquid and the lid 128. At thesame time, hydrogen gas is generated in the cathode compartment and isaccumulated in a chamber region 192 above the liquid level in thatchamber and below the lid 128. As previously described, these gases arenaturally aspirated through lines 102 and 104 for transfer to the gasfeed system as a result of the pressure built up due to the generationof gases. Typically, a pressure of about 0.5 pounds will be developedwithin the chamber regions 190 and 192.

An optional pressure sensor 195 may be provided through the lid 128 tosense the pressure of the chlorine gas within chamber region 190, asmore fully described in Applicant's prior U.S. Pat. No. 4,097,356.

Preferably, the electrical powered system will be interconnected withonly one of the anodes and one of the cathodes, since it has been foundthat such an interconnection is sufficient for producing adequatequantities of chlorine gas for use in home pools. This interconnectionmay then be changed later when either the anode or cathode haveexperienced deterioration. Alternatively, the power source may beinterconnected with all three anodes and all three cathodes in the eventthat greater quantities of chlorine gas are desired.

Referring now to FIGS. 5 and 6, the gas feed system 60 of this inventionis illustrated with greater particularity. The gas feed includes a majorplastic body portion 65 which is essentially rectangular in verticalcross section, as shown in FIG. 5. By comparing FIGS. 5 and 6, it willbe seen that body portion 65 includes two end walls 66 and 67, two sidewalls 68 and 69, and a bottom wall 70, which rests upon a support stand71. A top closure lid 72 is seated along the top edge of the side andend walls to form an enclosed compartment to receive the chlorine andhydrogen gases from flow lines 102 and 104 and the water from couplingmember 50.

As discussed in connection with FIG. 1, a gas trap region 62 is formedby downwardly depending plate 64, which may be a plastic material andsecured in a suitable fashion to a lip region 73 formed on end wall 66.

Liquid coupling member 50 is secured to the other end 67 of the gashousing by a connector element 74 which includes an internal opening 75mating with a fluid flow opening 76 in end wall 67. The coupling member50 includes a body 51 having a first major internal flow opening 53extending laterally through the body member to establish fluidcommunication between flow line 30 and the flow opening 75 in connectorelement 74. Additionally, a secondary flow opening 55 branches off offlow opening 53 for supplying water to flow line 52 in order to supplywater to branch lines 54 and 56 and then to separate anode and cathodecompartments of the gas generator 100 as previously disclosed. Further,a port 57 extends vertically up from flow conduit 53 and terminates in athreaded opening 59 to receive a conventional pressure sensing device(not shown). Such a pressure sensing member may be interconnected, forexample, with the cathode electrical connection 206 by appropriateelectrical connections (not shown) in order to override the timerelement 202 and deactivate the gas generator in the event that apressure loss is experienced in flow line 53. With this arrangement,chlorine gas will not be supplied to gas trap 62 unless water can besupplied to the gas feed system to transport the chlorine gas into themajor body of water.

Inside the housing 65 a float controlled valve 80 is provided toregulate the flow of water into the gas feed system. This flow controlassembly forms no part of the present invention and is therefore shownsomewhat schematically as including a float member 81 rigidlyinterconnected with a pivotal arm 82 which is in turn rigidlyinterconnected with arm 83. A valving element 84 is connected to pivotalarm 83 to seat within either opening 76 or an alternative supplementarymember which may be interconnected in the interior of housing 65 formounting the float controlled valve assembly. As also shownschematically, the valve assembly is pivotally connected and supportedby internal support plate 85.

FIG. 6 illustrates the positions that conduits 32, 102 and 104 areinserted into the gas feed housing 65. FIG. 5 illustrates that theconduits 32, 102 and 104 extend into the interior of housing 65 abovethe gas trap region 62 and are curved downwardly to extend throughappropriate openings in plate 64 and into the gas trap 62.

In the operation of the gas feed assembly, water will be supplied to theinterior of housing 65 by way of flow line 30 in order to maintain adesired water level. As will be appreciated, this water level will beregulated by the float control assembly 80 such that when the waterlevel drops, float 81 will respond by pivoting arms 82 and 83 in acounterclockwise direction, unseating valve member 84 and accomodatingthe flow of water. Likewise, as the water level rises in the gas feedhousing 65, float 81 will rise to pivot arms 82 and 83 in a clockwisedirection to shut off the flow of water. During the supply of D.C.current to the gas generator, hydrogen and chlorine gases will besupplied to the gas trap region 62 by way of separate flow lines 102 and104. As the gases are introduced into this region, they are admixed withwater and flow out of housing 65 by flow conduit 32. As water and gasesexit through line 32, the water level in housing 65 drops and additionalwater is metered into the assembly by the manner previously disclosed inconnection with float valve 80.

As will be appreciated by those skilled in the art, variousmodifications may be made to the disclosed embodiment without departingfrom the true scope of the invention. For example, the configuration ofthe gas trap 62 may be varied to take on a conical shape formed by aseparate component placed within the gas feed system, such that thegases would be conveyed into the conical shaped chamber and water couldflow into the bottom of the conical member to convey the gases with thewater back to the main body of water.

Alternative power means and control systems could be employed to achievethe same results as provided in the present invention. As will beappreciated by comparing the present drawings and applicant's designpatent application Ser. No. 019,850, the top control portion of the gasgenerator is not illustrated in this application for purposes ofconciseness. The position or arrangement of the control means could bevaried, for example, to include a chlorine sensor as set forth inapplicant's prior U.S. Pat. No. 4,097,356 to replace the timer control202.

The present embodiment has been described primarily as being formed ofplastic material, but other materials such as fiberglass can beemployed. The primary consideration is that such other materials not bedeteriorated by sodium hydroxide or chlorine.

Other more minor changes may also be made. For example, the valvearrangement within the gas feed may be modified as desired. A shield maybe provided around the anode, in the manner as disclosed in Applicant'sprior U.S. Pat. No. 4,097,356. Additionally, cooling means may beprovided internally of the gas generator to reduce the temperature ofthe electrolytic solution, particularly in embodiments where thegenerator is increased in size to produce greater quantities ofchlorine.

Having therefore completely and sufficiently described my invention, Inow claim:
 1. In a method of injecting chlorine into a desired stream ofwater, the steps of:(a) simultaneously, electrolytically generatingchlorine gas and hydrogen gas within an electrolytic cell comprising ananode and a cathode immersed in an aqueous electrolytic solution; (b)collecting the chlorine and hydrogen gas in respective separate regionsin the electrolytic cell above the electrolytic solution; (c) inresponse to the naturally occuring pressure developed by the generationand collection of gases in Steps (a) and (b); separately conveying thechlorine and hydrogen gases essentially free of electrolytic solutionthrough two individual conduits to a gas feed system including anenclosed housing and an interior chamber into which the gases aredirectly conveyed by said two conduits; (d) flowing at least a portionof said desired stream of water into the enclosed housing of the gasfeed system and into the interior chamber; and then (e) flowing thewater, chlorine and hydrogen from said interior chamber to the desiredstream of water.
 2. The method as defined in claim 1, wherein Step (c)is characterized by conveying the hydrogen gas through an enclosedfiltering chamber before flowing the gas into the interior chamber ofthe gas feed, in order to remove at least some of the sodium hydroxideentrained in the gaseous hydrogen flow.
 3. The method as defined inclaim 1, wherein the desired stream of water is from a swimming pool,characterized by intermittently and selectively generating the chlorineand hydrogen for supply to the gas feed system, and by diverting a partof the water from the pool filtration circulation cycle to the gas feedsystem.
 4. The method as defined in claim 3, further including the stepof sensing the pressure of the water supplied to the gas feed system,and deactivating the electrolytic cell in the event that the waterpressure drops below a predetermined, selected value.
 5. The method asdefined in claim 3, characterized by separating the electrolytic cellinto two separate regions by an ion-permeable membrane to define twoseparate electrolytic chambers for separate aqueous electrolyticsolutions.
 6. The method as defined in claim 5, further including thestep of selectively diverting a portion of the water from the poolfiltration cycle for filling the separate electrolytic chambers.
 7. Themethod as defined in claim 3, characterized by intermittentlyintroducing water from the pool circulation cycle into the gas feedsystem in order to maintain the water level at essentially apredetermined level, such that the introduction of water into the gasfeed system is in response to water flowing out of the gas feed systemthrough said interior chamber and back to the pool filtration cycle. 8.A chlorine generation and supply assembly including an electrolytic cellhaving a housing enclosing an anode and cathode for the generation ofgases, including chlorine, and means for accommodating the aspiration ofthe gases from the housing, the improvement of:a gas-feed system forfluid communication with the electrolytic cell and including a housingfor receiving water from a body of water to be chlorinated, the housingincluding (a) an enclosed major chamber for receiving the flow of waterand an enclosed minor chamber to receive both the gaseous chlorine andthe flow of water, the major and minor chambers being in fluidcommunication such that the water supplied to the major chamber mayfreely flow into the minor chamber, and the minor chamber being formedas a compartment in the major chamber; (b) means for supplying a streamof water to the major chamber; (c) a control valve for regulating theflow of water from the supply means to the major chamber in order tomaintain an essentially constant volume of water within the housing; (d)a first conduit in fluid communication with the minor chamber forsupplying the gaseous chlorine thereto from the electrolytic cell, and(e) a second conduit in fluid communication with the minor chamber forconveying water and intermixed chlorine from the housing to the desiredbody of water.
 9. The assembly as defined in claim 8, characterized bythe gas feed housing including a top closure member for a major bodycomponent having a bottom, two sides and two ends, the admixing chamberbeing formed at a first end of the housing body by a plate attached tothat end at a position toward the top of the housing body such that theplate extends downwardly and toward the other housing end, with theplate terminating above the bottom to form said admixing chamber betweensaid plate and said first end and to provide a passageway for water intothe admixing chamber between the bottom of the plate and the bottom ofthe housing body.
 10. The assembly as defined in claim 9, wherein theelectrolytic cell is divided into two separate regions on each side of aseparator divider formed in part by an ion permeable membrane such thatan anode and cathode are on opposite sides of the membrane, the furtherimprovement of a conduit extending from each respective region of thecell housing and to the admixing chamber of the gas feed system toseparately conduct the gases generated on each side of the electrolyticcell.
 11. The assembly as defined in claim 10, wherein the ion permeablemembrane is formed of a perfluorosulfonic acid polymer.
 12. The assemblyas defined in claim 11, wherein the electrolytic cell further includes atimer control for selectively activating the cell by supplying electriccurrent thereto.
 13. The assembly as defined in claim 10, characterizedby the cell including three anodes and three cathodes threadedly securedto the bottom of the cell housing.
 14. The assembly as defined in claim8, wherein the electrolytic cell is divided into two separate regions oneach side of a separator divider formed in part by an ion permeablemembrane such that the anode and cathode are on opposite sides of themembrane, the further improvement of a conduit extending from eachrespective region of the cell housing and to the admixing chamber of thegas feed system to separately conduct the gases generated on each sideof the electrolytic cell.
 15. The assembly as defined in claim 14,wherein chlorine is generated on one side of the cell and hydrogen isgenerated on the other side of the cell, the further improvement of afilter interposed along the conduit conveying the hydrogen from the cellto the gas feed assembly to remove at least some of the sodium hydroxidebeing conveyed with the hydrogen, the filter including an enclosurereceiving a conduit portion extending from the cell to the filter and aseparate conduit portion extending from the filter to the gas feedassembly, such that hydrogen and entrained moisture are conveyed to thefilter, moisture with entrained sodium hydroxide are deposited in thefilter, and hydrogen gas is conveyed on to the gas feed assembly. 16.The assembly as defined in claim 8, wherein a liquid communicationcoupling is provided on the gas-feed system to receive water from asource, the coupling including the first flow line for supplying waterto the gas-feed system and a second flow line for supplying water toeach of the active half-cells of the electrolytic cell.
 17. The assemblyas defined in claim 16, characterized by the cell being divided into twoseparate regions on each side of a separator divider formed in part byan ion permeable membrane such that the anode and cathode are onopposite sides of the membrane, the further improvement of a flowconduit extending from the second flow line of the liquid coupling andthen branching into two sections which extend to the cell housing oneach side of the separator divider, and a dual-purpose valve beingprovided at the point of interconnection between the branch lines andthe cell housing for (a) selectively supplying water to the respectiveregions of the cell and (b) simultaneously venting the respectiveregions of pressure as water is supplied thereto.
 18. The assembly asdefined in claim 16, wherein the liquid coupling further includes a portto receive a means for sensing the liquid water pressure from thesource.
 19. The assembly as defined in claim 16, further including afloat controlled valve which regulates the flow of water from said firstflow line to maintain an essentially constant water level in the gasfeed system.
 20. The assembly as defined in claim 14, characterized inthat said second conduit is in communication with the minor chamber by afirst port in the housing and the conduits from the respective regionsof the cell are in communication with the minor chamber by second andthird ports spaced from said first port.
 21. The assembly as defined inclaim 14, characterized in that the first conduit is in fluidcommunication with the minor chamber by an unrestricted port free of anyflow regulation means.
 22. The method as defined in claim 1,characterized in Step (c) by the chlorine and hydrogen gases beingconveyed through unrestricted, spaced ports in the gas feed system freeof any flow regulation means.